1. Field of the Invention
The present invention relates to a punch press system, and in particular to a turret punch press system including a turret punch press and an automatic tool changing apparatus.
2. Prior Art
An example of a conventional turret punch press system is shown in U.S. Pat. No. 5,215,513. This system includes a turret punch press equipped with removable tools for performing punch processing in a sheet workpiece. The system also includes a tool changing apparatus, and a tool storage for storing a large number of tools. The tool changing apparatus removes a tool from the turret punch press, and transfers the same to the tool storage. Further, the apparatus takes out a new tool from the tool storage, and transfers the same to the turret punch press. The tool changing apparatus disclosed in U.S. Pat. No. 5,215,513 particularly includes a carriage movable between the turret punch press and the tool storage. Further, the turret punch press, the tool changing apparatus, and the tool storage are controlled by conventional NC control devices.
In the turret punch press system described above, a large number of tools stored in the tool storage are automatically supplied to the turret punch press, so that a variety of punchings can be automatically performed in a sheet workpiece by using a variety of tools.
In the conventional turret punch press system, however, control programs for the tool changing device and the tool storage are uniquely determined in relation to the control program for the turret punch press. Here the latter control program depends on the kind of the punch processing performed by the turret punch press. Thus each time the kind of the punch processing performed by the turret punch press is changed, the control programs for the tool changing device and the tool storage were changed. Such frequent changing of the control program was troublesome to an operator.
Further, when the tool of the turret punch press has performed a large number of punchings, the tools are worn away. Thus, the tools need to be ground to be sharpened. In a conventional turret punch press, in order to see whether the tools need to be ground, an operator examines the condition or the precision of punched holes formed by the tools. When the punched holes have dull edges, the punch tools are removed from the system and ground. However, the examination of the tool and the determination of the grinding of the tool was troublesome to the operator.